This invention relates in general to antifriction bearings and, more particularly, to an antifriction bearing having an outer race provided with external threads to facilitate adjustment of the bearing.
Antifriction bearings organized in pairs support shafts in a wide variety of equipment. Typically each bearing has an outer race fitted into a housing, an inner race around a shaft, and rolling elements organized in a single row between the two races. The rolling elements contact the races along raceways that are inclined with respect to the axis of the bearings, and the raceways of each bearing, while being inclined in the same direction, are inclined in the direction opposite to the inclination of the raceways of the other bearing. In other words, the two bearings that support the shaft are mounted in opposition. This enables the bearings to be adjusted against each other between end play, where the bearings have internal clearances, and preload where no internal clearances and good shaft stability exists.
Adjustment is achieved by controlling the axial positions of the races. Indeed, axial displacement of any one of the four races will change the setting of the bearings. Some bearing arrangements control the setting at the outer races—or at least at one of the outer races. And one way to control the axial position of an outer race is to provide it with an external thread that engages an internal thread in the housing. Thus, by rotating the threaded outer race in its threaded seat, one can adjust the setting for the bearings. See U.S patent application Ser. No. 2005/0063629-A1, published Mar. 24, 2005.
Tapered roller bearings represent one type of bearing that lends itself to adjustment. And automotive differentials make ample use of tapered roller bearings. Such bearings support pinion shafts in differentials and also fit around stub shafts on the ends of the carriers that deliver torque to the axle shafts. In the forward axle of a tandem axle arrangement they support the input shaft and the through shaft. As to any one of these shafts, one bearing is adjusted against another to control the setting of the two bearings.